20397792500 has 30 divisors (see below), whose sum is σ = 44605898106. Its totient is φ = 8159116000.

The previous prime is 20397792479. The next prime is 20397792511. The reversal of 20397792500 is 529779302.

It is a happy number.

It can be written as a sum of positive squares in 5 ways, for example, as 12987337444 + 7410455056 = 113962^2 + 86084^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 4077059 + ... + 4082058.

Almost surely, 2^20397792500 is an apocalyptic number.

20397792500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20397792500 is an abundant number, since it is smaller than the sum of its proper divisors (24208105606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20397792500 is an equidigital number, since it uses as much as digits as its factorization.

20397792500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8159141 (or 8159124 counting only the distinct ones).

The product of its (nonzero) digits is 238140, while the sum is 44.

The spelling of 20397792500 in words is "twenty billion, three hundred ninety-seven million, seven hundred ninety-two thousand, five hundred".